Scaling of the urban heat island intensity using time-dependent energy balance

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

The urban heat island intensity (UHI) can be scaled with the urban length scale and the wind speed, through the time-dependent energy balance. The heating of the urban surfaces during the daytime sets the initial temperature, and this overheating is dissipated during the night-time through mean convection motion over the urban surface. The energy balance shows that this cooling effect can be quantified in an exponential decay in time. The minimum temperature reached at the end of this cooling period corresponds to the UHI, which increases with increasing urban length scale and decreasing wind speed. The temporal data for Phoenix, Arizona are reasonably accurately traced by this model, for the time period, from 1983 to 2010 during which Phoenix has undergone substantial expansion and therefore an increase in the urban length scale. Comparisons with the data in several cities around the world also yield quantitatively correct results for the effect of the wind speed. This model does require one correction factor to account for different urban topology in different cities. Thus, using a small number of readily available data for the urban length scale and the wind speed, the UHI intensity can be described with possible predictions for future trends.

Original languageEnglish (US)
Pages (from-to)16-24
Number of pages9
JournalUrban Climate
Volume2
DOIs
StatePublished - Dec 2012

Fingerprint

heat island
scaling
energy balance
heat
wind velocity
energy
cooling
heat pump
topology
temperature
convection
heating
time
trend
prediction
city
effect

Keywords

  • Energy balance
  • Urban heat island

ASJC Scopus subject areas

  • Atmospheric Science
  • Environmental Science (miscellaneous)
  • Geography, Planning and Development
  • Urban Studies

Cite this

Scaling of the urban heat island intensity using time-dependent energy balance. / Lee, Taewoo; Lee, J. Y.; Wang, Zhihua.

In: Urban Climate, Vol. 2, 12.2012, p. 16-24.

Research output: Contribution to journalArticle

@article{0e1c7af36af3441c8567be96c19e3cfa,
title = "Scaling of the urban heat island intensity using time-dependent energy balance",
abstract = "The urban heat island intensity (UHI) can be scaled with the urban length scale and the wind speed, through the time-dependent energy balance. The heating of the urban surfaces during the daytime sets the initial temperature, and this overheating is dissipated during the night-time through mean convection motion over the urban surface. The energy balance shows that this cooling effect can be quantified in an exponential decay in time. The minimum temperature reached at the end of this cooling period corresponds to the UHI, which increases with increasing urban length scale and decreasing wind speed. The temporal data for Phoenix, Arizona are reasonably accurately traced by this model, for the time period, from 1983 to 2010 during which Phoenix has undergone substantial expansion and therefore an increase in the urban length scale. Comparisons with the data in several cities around the world also yield quantitatively correct results for the effect of the wind speed. This model does require one correction factor to account for different urban topology in different cities. Thus, using a small number of readily available data for the urban length scale and the wind speed, the UHI intensity can be described with possible predictions for future trends.",
keywords = "Energy balance, Urban heat island",
author = "Taewoo Lee and Lee, {J. Y.} and Zhihua Wang",
year = "2012",
month = "12",
doi = "10.1016/j.uclim.2012.10.005",
language = "English (US)",
volume = "2",
pages = "16--24",
journal = "Urban Climate",
issn = "2212-0955",
publisher = "Elsevier BV",

}

TY - JOUR

T1 - Scaling of the urban heat island intensity using time-dependent energy balance

AU - Lee, Taewoo

AU - Lee, J. Y.

AU - Wang, Zhihua

PY - 2012/12

Y1 - 2012/12

N2 - The urban heat island intensity (UHI) can be scaled with the urban length scale and the wind speed, through the time-dependent energy balance. The heating of the urban surfaces during the daytime sets the initial temperature, and this overheating is dissipated during the night-time through mean convection motion over the urban surface. The energy balance shows that this cooling effect can be quantified in an exponential decay in time. The minimum temperature reached at the end of this cooling period corresponds to the UHI, which increases with increasing urban length scale and decreasing wind speed. The temporal data for Phoenix, Arizona are reasonably accurately traced by this model, for the time period, from 1983 to 2010 during which Phoenix has undergone substantial expansion and therefore an increase in the urban length scale. Comparisons with the data in several cities around the world also yield quantitatively correct results for the effect of the wind speed. This model does require one correction factor to account for different urban topology in different cities. Thus, using a small number of readily available data for the urban length scale and the wind speed, the UHI intensity can be described with possible predictions for future trends.

AB - The urban heat island intensity (UHI) can be scaled with the urban length scale and the wind speed, through the time-dependent energy balance. The heating of the urban surfaces during the daytime sets the initial temperature, and this overheating is dissipated during the night-time through mean convection motion over the urban surface. The energy balance shows that this cooling effect can be quantified in an exponential decay in time. The minimum temperature reached at the end of this cooling period corresponds to the UHI, which increases with increasing urban length scale and decreasing wind speed. The temporal data for Phoenix, Arizona are reasonably accurately traced by this model, for the time period, from 1983 to 2010 during which Phoenix has undergone substantial expansion and therefore an increase in the urban length scale. Comparisons with the data in several cities around the world also yield quantitatively correct results for the effect of the wind speed. This model does require one correction factor to account for different urban topology in different cities. Thus, using a small number of readily available data for the urban length scale and the wind speed, the UHI intensity can be described with possible predictions for future trends.

KW - Energy balance

KW - Urban heat island

UR - http://www.scopus.com/inward/record.url?scp=84870347857&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84870347857&partnerID=8YFLogxK

U2 - 10.1016/j.uclim.2012.10.005

DO - 10.1016/j.uclim.2012.10.005

M3 - Article

AN - SCOPUS:84870347857

VL - 2

SP - 16

EP - 24

JO - Urban Climate

JF - Urban Climate

SN - 2212-0955

ER -